Certain infections may 'increase your risk' of cancer, says BBC doctor

Certain infections may 'increase your risk' of cancer, says BBC doctor Various bugs have the chance of developing into cancer, a report claims A TV doctor says some infections may lead to cancer. On BBC Morning Live, Dr Xand van Tulleken recently investigated the link between common pathogens and oncogenesis, reassuring viewers that cancer itself is not contagious, but clarifying that certain untreated infections can significantly increase your risk of developing cancer. It comes as reports claim one in eight cancer cases are "caused by infections" that thousands of people get every year. Appearing on the BBC show this week, Dr Xand said the claims come from a World Health Organisation document and do discuss the possible association between developing an infection and cancer. While cancer itself is not contagious, certain viruses, bacteria, and parasites can cause changes in the body that lead to cancer over time. This discussion directly aligns with a study published in The Lancet Oncology. The research revealed that roughly 12% of all new cancer cases worldwide are tied directly to infections and 2.3 million cases were caused by infections in 2024. He said: "You cannot 'catch' cancer from people who already have cancer. Cancer is already such a stigmatised illness... you are at no risk to give [someone with cancer] a hug." Dr Xand stressed that certain infections "will not always give you cancer", but they may "increase your risk". He likened it to cigarettes - they do not directly cause cancer, but do increase your risk of developing it. The media medic claims that an example of this in action is HPV (a common sexually transmitted infection) that is "strongly associated" with cervical cancer. This infection has the possible chance of causing cancer, if left untreated, by damaging the DNA of cervical cells and stopping them from dying normally. Dr Xand claims this risk has been minimised through years of research that led to the development of a vaccine. Millions of women have been protected from this, with "almost 90%" of cervical cancer cases falling in the vaccinated population. What infections can potentially lead to cancer? Dr Xand claims the "most common" infection that has been linked to cancer is called H Pylori. The doctor said people may have been tested for this if they have ever had a stomach ulcer or gastritis. People could be at greater risk of developing cancer because of the constant "damage and repair" cycle that stomach ulcers cause. Hepatitis B and C were also listed as infections that have known links to cancer. The Epstein-Barr virus, commonly linked to glandular fever, was also listed in the report. For most problems, Dr Xand claims the risk is greatly minimised by vaccinations. He said: "These bugs are very common. It is interesting that they are associated with cancer, in terms of public health, but it shouldn't change your everyday behaviour. What are the key pathogens responsible? - Helicobacter pylori (H. pylori): Responsible for ~760,000 cases (about 4% of global cancers), primarily stomach (gastric) cancer. - Human Papillomavirus (HPV): Responsible for ~750,000 cases (about 4%), primarily cervical, anal, and head/neck cancers. - Hepatitis B Virus (HBV): Responsible for ~360,000 cases (about 2%), primarily liver cancer. - Epstein-Barr Virus (EBV): Responsible for ~260,000 cases (about 1%), linked to nasopharyngeal, gastric, and Hodgkin lymphoma. - Hepatitis C Virus (HCV): Responsible for under 1% of cases, primarily liver cancer. Many of these cancers are preventable through vaccination (such as the HPV and Hepatitis B vaccines) or antibiotic and antiviral treatments (such as curing H. pylori or hepatitis C). However, about 75% of these infection-linked cases occur in low- and middle-income countries due to limited access to screening and vaccines. Regular tests (such as cervical screenings) can catch precancerous changes early.